The Experts In All Aspects Of Backflow Prevention. Plumbers & Gasfitters - Knoxfield, VIC . Service: Annual Testing, Backflow Prevention, Backflow Testing, Installation, Water Lines, Water Mains, Water Tapping. Specialty: Fire Services, Greywater Diversion. Item: Rainwater Tanks. Service Option: After Hours Service, Free Quotes, Inspections, Maintenance Contracts. Payment Concern: Fixed Pricing. Part: Air Gaps, Backflow Prevention Devices, Break Tanks, Double Check Valves, Pressure Vacuum Breakers, Reduced Pressure Zone Devices, Valves. Payment Method: Cheques, EFT. Type: Commercial, Industrial, Residential. Assurance: Certified, Licensed